<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
</head>
<body>
    <button>按钮</button>
    <script>
        let btn = document.querySelector('button');
        let fn = (e)=>{
            console.log(e);
        }
        btn.onclick = fn;
        let resolve = (value)=>{ // resolve: xxxfff111

        }
        let reject = (reason)=>{// reject: xxxfff222

        }
        rs.then(v=>{
            resolve(v)
        },r=>{
            reject(r);
        })

        rs.then(resolve,reject);
    </script>
</body>
</html>